gnu: gcc@6: Fix building with glibc@2.26.

* gnu/packages/gcc.scm (gcc@6)[source]: Add snippet to adjust
linux-unwind.h to changes in glibc@2.26.  Add patch.
* gnu/packages/patches/gcc-libsanitizer-fix.patch: New file.
* gnu/local.mk (dist_patch_DATA): Register it.

3 files changed, 129 insertions, 2 deletions

diff --git a/gnu/local.mk b/gnu/local.mk
index 289bbad164..6308a81e66 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -650,6 +650,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/gcc-asan-missing-include.patch		\
   %D%/packages/patches/gcc-cross-environment-variables.patch	\
   %D%/packages/patches/gcc-fix-texi2pod.patch			\
+  %D%/packages/patches/gcc-libsanitizer-fix.patch		\
   %D%/packages/patches/gcc-libvtv-runpath.patch			\
   %D%/packages/patches/gcc-strmov-store-file-names.patch	\
   %D%/packages/patches/gcc-4-compile-with-gcc-5.patch		 \
diff --git a/gnu/packages/gcc.scm b/gnu/packages/gcc.scm
index 020d2a7138..350a9bd3fb 100644
--- a/gnu/packages/gcc.scm
+++ b/gnu/packages/gcc.scm
@@ -444,10 +444,23 @@ Go.  It also includes runtime support libraries for these languages.")
               (sha256
                (base32
                 "1m0lr7938lw5d773dkvwld90hjlcq2282517d1gwvrfzmwgg42w5"))
-              (patches (search-patches "gcc-strmov-store-file-names.patch"
+              (patches (search-patches "gcc-libsanitizer-fix.patch"
+                                       "gcc-strmov-store-file-names.patch"
                                        "gcc-6-source-date-epoch-1.patch"
                                        "gcc-6-source-date-epoch-2.patch"
-                                       "gcc-5.0-libvtv-runpath.patch"))))
+                                       "gcc-5.0-libvtv-runpath.patch"))
+              (modules '((guix build utils)))
+              ;; This is required for building with glibc-2.26.
+              ;; This can be removed when gcc-6.5.0 is released.
+              ;; https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81712
+              (snippet
+               '(for-each
+                  (lambda (dir)
+                    (substitute* (string-append "libgcc/config/"
+                                                dir "/linux-unwind.h")
+                      (("struct ucontext") "ucontext_t")))
+                  '("aarch64" "alpha" "bfin" "i386" "m68k" "nios2"
+                    "pa" "sh" "tilepro" "xtensa")))))
     (inputs
      `(("isl" ,isl)
        ,@(package-inputs gcc-4.7)))))
diff --git a/gnu/packages/patches/gcc-libsanitizer-fix.patch b/gnu/packages/patches/gcc-libsanitizer-fix.patch
new file mode 100644
index 0000000000..67aa44bed4
--- /dev/null
+++ b/gnu/packages/patches/gcc-libsanitizer-fix.patch
@@ -0,0 +1,113 @@
+https://gcc.gnu.org/git/?p=gcc.git;a=patch;h=8937b94d1a643fd9760714642296d034a45254a8
+https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81066
+
+This patch can be removed when gcc-6.5.0 is released
+
+From 8937b94d1a643fd9760714642296d034a45254a8 Mon Sep 17 00:00:00 2001
+From: doko <doko@138bc75d-0d04-0410-961f-82ee72b054a4>
+Date: Thu, 7 Sep 2017 07:15:24 +0000
+Subject: [PATCH] 2017-09-07  Matthias Klose  <doko@ubuntu.com>
+
+        Backported from mainline
+        2017-07-14  Jakub Jelinek  <jakub@redhat.com>
+
+        PR sanitizer/81066
+        * sanitizer_common/sanitizer_linux.h: Cherry-pick upstream r307969.
+        * sanitizer_common/sanitizer_linux.cc: Likewise.
+        * sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc: Likewise.
+        * tsan/tsan_platform_linux.cc: Likewise.
+
+
+git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-6-branch@251828 138bc75d-0d04-0410-961f-82ee72b054a4
+---
+ libsanitizer/ChangeLog                                        | 11 +++++++++++
+ libsanitizer/sanitizer_common/sanitizer_linux.cc              |  3 +--
+ libsanitizer/sanitizer_common/sanitizer_linux.h               |  4 +---
+ .../sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc  |  2 +-
+ libsanitizer/tsan/tsan_platform_linux.cc                      |  2 +-
+ 5 files changed, 15 insertions(+), 7 deletions(-)
+
+diff --git a/libsanitizer/ChangeLog b/libsanitizer/ChangeLog
+index 252cd09..d988b28 100644
+--- a/libsanitizer/ChangeLog
++++ b/libsanitizer/ChangeLog
+@@ -1,3 +1,14 @@
++2017-09-07  Matthias Klose  <doko@ubuntu.com>
++
++	Backported from mainline
++	2017-07-14  Jakub Jelinek  <jakub@redhat.com>
++
++	PR sanitizer/81066
++	* sanitizer_common/sanitizer_linux.h: Cherry-pick upstream r307969.
++	* sanitizer_common/sanitizer_linux.cc: Likewise.
++	* sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc: Likewise.
++	* tsan/tsan_platform_linux.cc: Likewise.
++
+ 2017-07-04  Release Manager
+ 
+ 	* GCC 6.4.0 released.
+diff --git a/libsanitizer/sanitizer_common/sanitizer_linux.cc b/libsanitizer/sanitizer_common/sanitizer_linux.cc
+index 2cefa20..223d9c6 100644
+--- a/libsanitizer/sanitizer_common/sanitizer_linux.cc
++++ b/libsanitizer/sanitizer_common/sanitizer_linux.cc
+@@ -546,8 +546,7 @@ uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) {
+ }
+ #endif
+ 
+-uptr internal_sigaltstack(const struct sigaltstack *ss,
+-                         struct sigaltstack *oss) {
++uptr internal_sigaltstack(const void *ss, void *oss) {
+   return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss);
+ }
+ 
+diff --git a/libsanitizer/sanitizer_common/sanitizer_linux.h b/libsanitizer/sanitizer_common/sanitizer_linux.h
+index 4497702..1594058 100644
+--- a/libsanitizer/sanitizer_common/sanitizer_linux.h
++++ b/libsanitizer/sanitizer_common/sanitizer_linux.h
+@@ -19,7 +19,6 @@
+ #include "sanitizer_platform_limits_posix.h"
+ 
+ struct link_map;  // Opaque type returned by dlopen().
+-struct sigaltstack;
+ 
+ namespace __sanitizer {
+ // Dirent structure for getdents(). Note that this structure is different from
+@@ -28,8 +27,7 @@ struct linux_dirent;
+ 
+ // Syscall wrappers.
+ uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count);
+-uptr internal_sigaltstack(const struct sigaltstack* ss,
+-                          struct sigaltstack* oss);
++uptr internal_sigaltstack(const void* ss, void* oss);
+ uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
+     __sanitizer_sigset_t *oldset);
+ void internal_sigfillset(__sanitizer_sigset_t *set);
+diff --git a/libsanitizer/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc b/libsanitizer/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc
+index c919e4f..014162af 100644
+--- a/libsanitizer/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc
++++ b/libsanitizer/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc
+@@ -267,7 +267,7 @@ static int TracerThread(void* argument) {
+ 
+   // Alternate stack for signal handling.
+   InternalScopedBuffer<char> handler_stack_memory(kHandlerStackSize);
+-  struct sigaltstack handler_stack;
++  stack_t handler_stack;
+   internal_memset(&handler_stack, 0, sizeof(handler_stack));
+   handler_stack.ss_sp = handler_stack_memory.data();
+   handler_stack.ss_size = kHandlerStackSize;
+diff --git a/libsanitizer/tsan/tsan_platform_linux.cc b/libsanitizer/tsan/tsan_platform_linux.cc
+index 09cec5f..908f4fe 100644
+--- a/libsanitizer/tsan/tsan_platform_linux.cc
++++ b/libsanitizer/tsan/tsan_platform_linux.cc
+@@ -291,7 +291,7 @@ bool IsGlobalVar(uptr addr) {
+ int ExtractResolvFDs(void *state, int *fds, int nfd) {
+ #if SANITIZER_LINUX
+   int cnt = 0;
+-  __res_state *statp = (__res_state*)state;
++  struct __res_state *statp = (struct __res_state*)state;
+   for (int i = 0; i < MAXNS && cnt < nfd; i++) {
+     if (statp->_u._ext.nsaddrs[i] && statp->_u._ext.nssocks[i] != -1)
+       fds[cnt++] = statp->_u._ext.nssocks[i];
+-- 
+2.9.3
+